1049. Adenosine Deaminase Levels in Pleural Effusions Caused by Coccidioidomycosis 
Session: Poster Abstract Session: Fungal Diagnosis
Saturday, October 22, 2011
Room: Poster Hall B1
Background: Lymphocyte predominant pleural effusions are a common clinical problem yet the causal etiology may be difficult to diagnose in the absence of pleural biopsy.  In some cases pleural fluid adenosine deaminase (ADA) is useful and suggests tuberculous pleurisy when levels exceed 50 IU/L.  Despite a lack of definitive evidence several reports have speculated that elevated ADA levels may also be seen in other lymphocyte-rich pleural effusions including those caused by coccidioidomycosis.

Methods: Forty consecutive patients who underwent pleural fluid coccidioidal antibody testing were included for review.  Chart abstraction was performed to gather patient demographic variables, clinical history, serum and pleural fluid laboratory values, and to assess outcomes.  Established EORTC/MSG criteria were used for the diagnosis of coccidioidomycosis.  All pleural fluid samples were kept frozen until ADA testing at a centralized laboratory (ARUP, Salt Lake City, UT).

Results: The pleural fluid samples obtained from 13 patients with active coccidioidomycosis (5 proven cases, 8 probable) contained mean ADA levels (+SD) of 8.5 + 8.8 IU/L (range, 0-28.6 IU/L) while the 27 samples from patients ultimately found to have non-coccidioidal diagnoses contained mean ADA levels (+SD) of 8.6 + 15.4 IU/L (range, 0-80.8 IU/L).  No statistically significant difference was observed between these groups (p=0.97).  Only one sample in the non-coccidioidal group exhibited an ADA level exceeding 50 IU/L and this patient was found to have a complicated parapneumonic effusion from bacterial pneumonia.  No patients in this study had a diagnosis of tuberculosis.

Conclusion: Pleural fluid ADA levels have no role in the diagnosis of coccidioidal pleural effusions.  Despite recent speculation to the contrary, we observed pleural fluid ADA levels less than 50 IU/L in all patients with proven or probable coccidioidomycosis and values did not significantly differ from pleural fluid ADA values of patients with non-coccidioidal diagnoses.


Subject Category: M. Mycology including clinical and basic studies of fungal infections

George R. Thompson III, MD, Medical Microbiology and Immunology, University of California-Davis, Davis, CA, Derek Bays, University of California - Davis, Davis, CA, Shobha Sharma, DO, Fresno Med Ctr, Brooklyn, NY, Michael Davis, Doctors Hospital of Manteca, Manteca, CA, Robert D. Libke, MD, Infectious Diseases, UCSF-Fresno, Fresno, CA and Demosthenes Pappagianis, MD, PhD, University of California School of Medicine, Davis, CA

Disclosures:

G. R. Thompson III, Pfizer: Investigator, Research support

D. Bays, None

S. Sharma, None

M. Davis, None

R. D. Libke, None

D. Pappagianis, None

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